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The following article describes the method that I have adopted over many years
and the one that has always proved successful. Other breeders may vary from
this method, and can be just as successful - there are no hard and fast rules.
Summertime - planning for the following Spring
You must start thinking about breeding as early as July or August of the year
before you intend to breed. The reason for this is that you must consider what
type of fish you want to breed; I would recommend, for the beginner, that a
singletail type fish is selected. It is wise not to try and deal with too many
varieties at once, so I would suggest that you choose just one or two types
and concentrate on them.
July and August is the best time to purchase fish, as this is the time when
the breeders are selling their surplus stock. One can buy six or more young
fish at a reasonable price and grow these on for the future. This also gives
you a good chance of getting both sexes from the same strain. The minimum number
of adult fish of one strain that I would recommend at this time would be two
females and three males, because it is very easy to lose one or two fish (for
numerous reasons, e.g. a long hard winter or when applying heat after the winter
when the fish have less resistance to disease). There is very little chance
of replacing fish in February or March.
Over-wintering of fish
The next stage is to feed the fish up, so that they have enough body mass to
see them through the winter and leave them strong enough to prepare for spawning
in the early Spring.
For those who keep their fish outside or in a fish house, you will notice that
at the end of October and into November your fish are beginning to slow down
and do not require the same amount of food. This is the time to 'clean' your
fish and separate the males and the females.
The solution that I use to clean the fish is one measure of Terramycin, 80
drops of Formaldehyde and 6 drops of copper sulphate in 4 gallons of water at
the right temperature and not forgetting the aeration. After the fish have been
in this solution for 20 minutes they are transferred into another container
of clean water. In the meantime, your tanks must be given a thorough cleansing
with bleach or Milton sterilizing fluid, but be sure that they are completely
rinsed out afterwards. (NOTE: omit cleaning if you do not feel confident about
it, or if you keep your fish in very clean conditions throughout the year).
For the next two, or two and a half months, the fish should receive practically
no food; perhaps a little live food (e.g. daphnia), if the weather is good,
but no dry food. If a lot of live food is not available, you could substitute
a high protein flake or pellet food. During this time, keep an eye on the fish:
if they appear to be suffering due to severe cold or very long periods of cold
weather, a little heat may be applied; this must be done very gradually and
no more than is absolutely necessary.
Springtime - preparing for breeding
If you decide, say, that you would like to put your fish together for spawning
on the 1st of April, then you must subtract six weeks from this date and that
gives you the date upon which you should start to raise the temperature by a
couple of degrees. Continue to do so each day until the temperature reaches
65 degrees Fahrenheit (18 degrees Centigrade). During this time the fish will
start looking for food: start with small quantities of live food and high protein
food, increasing the quantity as the temperature rises. Good aeration is required
and any excess food must be removed.
A 3 ft (90 cm) or a 4 ft (120 cm) tank is quite suitable for breeding and this
must be prepared at least a week before the fish are put together. If possible,
leave the tank empty for a couple of weeks, as this will kill off any disease;
otherwise, it must be thoroughly cleaned with bleach, Dettol or Milton fluid.
All traces of cleansing fluids must, however, be removed afterwards - keep rinsing
until all smells have gone. The tank can now be filled to a depth of six inches,
with a new air stone to aerate the water. In the meantime, the spawning medium
can be prepared: this can consist of bunches of nylon wool, unravelled nylon
pan scrubs, natural plants or nylon wool.
Parents: female left, male right. Spawned 24 March 2002
Selecting the fish
Now comes the big day when the fish can be selected and put together in the
breeding tank. First select the female: she should be heavy at the rear and
protruding on the left-hand side of the body. Try applying a little pressure
near the anal area, the body should be very soft.
Note: to sex goldfish, look for the following physical changes that occur at
the start of the breeding season: males develop breeding tubercles (white pimples) on the gill covers and
on the leading edge of the pectoral fins (see Finnage); females develop a deeper body as the fill with roe, and have a larger vent
(just before the anal fin) than the males.
Next is the turn of the males. It is advantageous to use two males to one female,
because this will give you a better fertility. They should be chosen for their
chasing ability and a good indication of their condition is the presence of
breeding tubercles on their gill plates and pectoral fins. The fish must then
be put through the same treatment as when bedding them down for the winter;
this is to make sure that they will not pass on any disease or parasites to
Spawning the fish
At all times the water temperature which the fish are being transferred into
should be at least 65 degrees Fahrenheit (18 degrees Centigrade). The ideal
time to introduce your fish into the breeding tank is in the early evening and
then the temperature should be raised gradually until it reaches 70 degrees
Fahrenheit (20 degrees Centigrade). Sometimes the fish may start chasing during
the first night and spawn the next day, but more often than not spawning takes
place a few days later. Fish can be stimulated by putting in fresh water from
a hose pipe under pressure; this is best carried out at night-time.
The fish will start to spawn early in the morning, and will generally carry
on until midday. Do not be in a hurry to separate them if they stop chasing
because they will periodically stop for a rest and then start again. Care must
be taken to guard against any fish that eat the eggs - these must be removed
as soon as possible.
Hatching the eggs
On completion of spawning, transfer the fish to a fresh tank with the water
at the same temperature; this can then be lowered gradually. On the second day,
you will notice that some of the eggs have a furry appearance; these are the
infertile eggs and can be ignored. The fertile eggs have a clear appearance
and after the first two days you will notice two little black eyes with a curved
black line, which is the body structure.
These eggs are very hard to see, but do not despair. If you can only find a
few, there will be many more when they hatch out and are free swimming. At 70
degrees Fahrenheit (20 degrees Centigrade) it will take 4 days for the eggs
to hatch out. Many of the fry will lie on the bottom of the tank, some will
cling to the sides of the tank and others will hang from the spawning medium.
The fry carry a food sack which will support them for two days. After this time
they will become free swimming and will start looking for food.
Feeding the fry
The best food at this stage is brine shrimp. This is cultivated by using a
large glass jar (e.g. a toffee jar) with 4 pints of water and 2 large tablespoons
full of common salt. Dissolve the salt in the water and add 2 teaspoons of brine
shrimp eggs. This must be kept at a temperature of between 75 and 80 degrees
Fahrenheit (23 - 25 degrees Centigrade) with strong aeration. It will take between
36 to 40 hours for the brine shrimp eggs to hatch. Next, remove the air stone
and leave the jar to stand for 10 minutes; the brine shrimp will settle at the
bottom of the jar and can be removed by siphoning through a fine tube and filtering
through a fine piece of nylon material.
After the first week, the spawning mops can be removed by turning them slowly
upside down and gently shaking to make sure that no fry are still attached.
It is very important to start culling the young fish as soon as possible, giving
the good fish more room and not wasting resources on substandard fish.
I trust that this information will be of value to you in your future breeding
W. H. Ramsden
Bill Ramsden is a leading fishkeeper and breeder who has judged
at all major shows throughout the Country for many years. He is a founder member
of the Northern Goldfish and Pondkeepers Society (1959) and has been President
of the Society for the past 30 years. He is also Chairman of the Nationwide
Goldfish Standards of Great Britain Committee.
Paul Winters was formerly joint secretary of BAS (2002). The photographs
are of his Bristol shubunkins raised in that year. Further photographs from
the 2003 season are presented below.
Fry at 12 days (left) and 26 days (right)
Young at 60 days
Young at 4 months
1 year old Bristol shubunkins
For detailed coverage of topics including obtaining good quality stock, selective
breeding for desired characteristics, the relative ease or difficulty of breeding
the different varieties, culling, feeding, keeping and housing their breeding
stock, see the Breeders' Notes under the following pages:
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